Drawer type cooking device

ABSTRACT

There is provided a drawer type cooking device which enables a user to easily check the inside of a heated object storage unit from the outside through a door glass by preventing water vapor generated from an object to be cooked during heating from contacting the inner surface of a door with a descending air flow along the inner surface of the door. During the heating operation of the cooking device, outside air sucked from a front surface lower portion of a cooking device body  1  and delivered into a heating chamber  3  by the operation of a cross-flow fan  13  passes through a gap passage  18  between a ceiling  16  and a splash cover  17  from a back surface upper portion of the heating chamber  3 , and flows as a descending air flow F 6  along the inner surface of a door glass  10  of a door  2   a . The descending air flow F 6  is exhausted from an exhaust unit  33  of the cooking device body  1  through an exhaust window unit  21  formed at the front end of a heated object storage unit  2   b . Water vapor generated from an object to be heated during cooking is caused not to contact the door glass  10  by the air curtain effect of the descending air flow F 6 , and thus, does not condense and adhere to fog the door glass  10.

The present application is based on and claims priority of Japanese patent application No. 2008-183044 filed on Jul. 14, 2008, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a drawer type cooking device in which a heated object storage unit can be drawn out of a heating chamber formed within a cooking device body by an operation of a door.

2. Description of the Related Art

FIG. 6 is a perspective view of a drawer type cooking device equivalent to the one previously proposed by the present applicant. A heating chamber 3 for cooking an object to be cooked (an object to be heated) is formed within a cooking device body 1. A drawer body 2 includes a door 2 a for opening and closing the heating chamber 3, and a heated object storage unit 2 b that is shaped like a container on which an object to be cooked can be loaded. The drawer body 2 is slidably disposed within the cooking device body 1 by a sliding mechanism 4, so that the drawer body 2 can be drawn out forward from the heating chamber 3 of the cooking device body 1, or can be pushed into the heating chamber 3. The sliding mechanism 4 is disposed at least on the right and left outer surfaces of the heating chamber 3, but may be also disposed on the bottom surface thereof. Since the sliding mechanism 4 is disposed outside the heating chamber 3, the heating chamber 3 can provide a wide space inside itself as the heated object storage unit 2 b. It is also not necessary to use an expensive component or material having high heat resistance and flame resistance for a movable rail, a fixed rail or the like, which constitute the sliding mechanism 4. Furthermore, there is no risk that the sliding mechanism 4 is affected by microwaves emitted in the heating chamber 3 and an electric discharge occurs due to the microwaves. A wired door glass 10 as a transparent plate for blocking the microwaves is fitted into the door 2 a such that a user can look into the heating chamber 3 from the outside when the door 2 a is closed.

Although not shown in detail in the drawing, the sliding mechanism 4 includes the fixed rail that is fixed to the cooking device body 1, and the movable rail that is mounted on the door 2 a to slide along the fixed rail. The drawer body 2 is slidably supported on the cooking device body 1 via the door 2 a and the sliding mechanism 4. A DC motor, for example, is provided as a driving mechanism to drive the sliding mechanism 4. Although not shown in detail in the drawing, a pinion that is rotated upon receiving a rotation output of the DC motor meshes with a rack that is mounted on the movable rail. When the pinion is rotated, the rack is moved linearly, so that the drawer body 2 is automatically driven via the sliding mechanism 4. The drawer body 2 can be thereby automatically drawn out and pushed in, which is especially preferable in a large cooking device.

The heated object storage unit 2 b has side walls on its right and left sides, and a back wall on its back side that is disposed inside the heating chamber 3 of the cooking device body 1. The heated object storage unit 2 b has an opening on its upper side, through which an object to be cooked can be put in and removed. The door 2 a is mounted on the front of the heated object storage unit 2 b. When an opening 3 a of the heating chamber 3 is closed by the door 2 a by pushing the drawer body 2 into the heating chamber 3, the inner space of the heating chamber 3 is hermetically sealed by the inner wall surfaces of the cooking device body 1 and the door 2 a, thereby preventing microwaves from leaking out. An operation unit 9 for allowing a user to open and close the door 2 a is provided on the upper side surface of the cooking device body 1. Although not shown in detail in the drawing, the operation unit 9 has an operation button, a control unit, and a display unit 5 for displaying operation contents.

As an example of a built-in kitchen apparatus, the present applicant has already proposed a built-in kitchen apparatus which combines an air supply unit and an exhaust unit, improves the efficiency of air supply and exhaust, improves the efficiency of cooling electric components and exhausting air in the chamber, and reduces the limits on the design and installation position of the kitchen apparatus (see Japanese Patent Laid-Open Publication No. 2008-8547). The kitchen apparatus is a drawer type cooking device such as a microwave oven whose heating chamber can be drawn out forward. In order to save the space required for the air supply unit and the exhaust unit for cooling, the air supply unit and the exhaust unit are collectively disposed in one of the upper, lower, left and right sides of a kitchen apparatus body in a manner such that an inlet of the air supply unit and an outlet of the exhaust unit open on the front surface. By separating the air supply unit and the exhaust unit on the same side, the mixing of supplied air and exhaust air is avoided, thereby improving the efficiency of air supply and exhaust, improving the efficiency of cooling electric components and exhausting air in the chamber, and raising the degree of freedom of the design and installation position of the kitchen apparatus.

In the kitchen apparatus, a cooling fan motor is provided at the back of the cooking device body. When the cooling fan motor is operated, outside air is sucked in from the front surface of the cooking device body. The air is partially blown to a magnetron, which is a microwave generating device, from the cooling fan motor, and the remaining air is blown to a high-voltage transformer, which is a device for generating a high voltage supplied to the magnetron, thereby respectively cooling the magnetron and the high-voltage transformer. The air flow cooling the magnetron flows into the heating chamber from the back surface. The air flowing into the heating chamber engulfs water vapor generated when an object to be cooked is heated, rises as moving forward within the heating chamber, and flows into an upper horizontal duct of the cooking device body 1. The air moves backward through the horizontal duct extending across the ceiling of the heating chamber, and then moves downward to a lower portion of the back surface of the cooking device body. After that, the air moves forward on the bottom surface of the cooking device body, and is exhausted from the exhaust unit in a lower portion of the front surface of the cooking device body.

In the drawer type cooking device, the supplied air sucked into the cooking device body is delivered into the heating chamber from the back surface of the heating chamber as described above. An air including the water vapor generated from the object to be cooked flows with the supplied air flow to flow toward the inner surface of the door that is disposed at the front. Thus, the water vapor comes into contact with the door glass and is cooled to cause condensation and adhesion of water droplets. Thus, the door glass is easily fogged up. Unless the water vapor generated from the object to be cooked is prevented from coming into contact with the door glass by changing the water vapor flow, it is very difficult to prevent the fogging of the door glass.

Generally, a cooking device such as a microwave oven has an air supply structure in which air is supplied into the heating chamber of the cooking device from either the right or left side surface. When air is supplied into the heating chamber from either the right or left side surface, the air can flow parallel to the door glass, and an air curtain function is provided. Accordingly, there is provided a structure in which the water vapor generated from the object to be cooked hardly comes into contact with the door glass. However, in the drawer type cooking device in which a drawer moving mechanism and a driving mechanism are stored on the right and left side surfaces of the heating chamber, it is very difficult to suck in air from the right or left side surface of the heating chamber.

It is a problem to be solved in the drawer type cooking device in which the supplied air is delivered into the heating chamber from the back surface of the heating chamber, to prevent the water vapor generated from the object to be cooked from being cooled in contact with the door glass to cause condensation and adhesion of water droplets, by causing the supplied air to flow parallel to the door glass and using the supplied air flow as an air curtain against said water vapor.

An object of the present invention is to provide a drawer type cooking device which enables a user to easily check the inside of a heated object storage unit from the outside through a door glass even when an object to be heated as an object to be cooked is cooked and water vapor is thereby generated, by preventing the water vapor of the object to be cooked from being cooled in contact with the inner surface of a door to cause condensation and adhesion of water droplets, with an air curtain effect of outside air flowing along the inner surface of the door.

SUMMARY OF THE INVENTION

In order to achieve the above object, a drawer type cooking device according to the present invention includes: a cooking device body having a heating chamber formed therein, the heating chamber having an opening to open at a front; a drawer body capable of being drawn out of and pushed into the heating chamber of the cooking device body; and a sliding mechanism slidably supporting the drawer body on the cooking device body outside the heating chamber; the drawer body including a heated object storage unit stored in the heating chamber in a pushed-in state with an object to be heated being loaded thereon, and a door mounted on a front end of the heated object storage unit and capable of closing the opening of the heating chamber in the pushed-in state, the door having a transparent plate for enabling a user to look into the heated object storage unit, wherein an air flow delivered into the heating chamber from a back surface of the heating chamber is caused to descend along an inner surface of the transparent plate of the door, and the descending air flow is exhausted along with water vapor generated by heating the object to be heated from an exhaust unit that opens at a front end of the cooking device body through an exhaust window unit that is formed at the front end of the heated object storage unit.

With the drawer type cooking device, the drawer body capable of being drawn out of and pushed into the heating chamber formed inside the cooking device body includes the heated object storage unit capable of storing the object to be heated, and the door integrally mounted on the front end of the heated object storage unit. When the drawer body is in the pushed-in state, the heated object storage unit is stored in the heating chamber, and the door can close the opening of the heating chamber.

The drawer body is slidably supported on the cooking device body by the sliding mechanism provided outside the heating chamber. A heating operation of the cooking device is performed when the drawer body is in the pushed-in state. Outside air delivered into the heating chamber from an upper portion of the back surface flows as the descending air flow along the inner surface of a door glass, and functions as an air curtain to block the flow of water vapor. The descending air flow is exhausted along with the water vapor generated from the object to be heated from the exhaust unit that opens at the front end of the cooking device body through the exhaust window unit formed at the front end of the heated object storage unit. Thus, the water vapor generated by heating the object to be heated is caused not to contact the transparent plate. The water vapor is not cooled in contact with the transparent plate to cause condensation and adhesion of water droplets.

The drawer type cooking device may further include a splash cover disposed with a gap between the splash cover and a ceiling wall of the heating chamber, wherein the air flow is guided to an upper portion of the inner surface of the door through the gap. The outside air delivered into the heating chamber from the back surface upper portion flows toward a front surface of the cooking device body through the gap formed between a top surface of the splash cover and a ceiling surface of the heating chamber, and further flows as the descending air flow along the inner surface of the door glass from a front end of the splash cover.

In the drawer type cooking device in which the splash cover is provided, when the drawer body is in the pushed-in state, a front end of the splash cover may occupy a position adjacent to the inner surface of the door, thereby forming a gap between the front end of the splash cover and the inner surface of the door to allow the descending air flow to flow down therefrom. Since the front terminal of the splash cover can be located at the position adjacent to the door, the air flow delivered into the heating chamber can be reliably caused to descend along the inner surface of the transparent plate from the gap formed between the front end of the splash cover and the inner surface of the door.

In the drawer type cooking device, the exhaust window unit may include an upright wall for guiding passage of the descending air flow at an edge along an exhaust window that is formed at the front end of the heated object storage unit. The exhaust window unit for exhausting the descending air flow is formed at the front end of the heated object storage unit. It is preferable that the descending air flow including the water vapor is smoothly exhausted through the exhaust window unit. Also, when water overflows from a food (the object to be heated) into the heating chamber, it is not preferable that the water flows out from the exhaust window unit. The upright wall is provided at the edge along the exhaust window in the heated object storage unit to meet such demands.

In the drawer type cooking device, the exhaust unit of the cooking device body may include an exhaust inlet formed in a bottom portion of the cooking device body at a position facing the exhaust window unit of the drawer body in the pushed-in state, and an exhaust outlet connected to the exhaust inlet to open at the front end of the cooking device body. The descending air flow flowing through the exhaust window unit of the drawer body flows into the exhaust inlet formed in the bottom portion of the cooking device body at the position facing the exhaust window unit, and is exhausted to the front from the exhaust outlet at the front end of the cooking device body.

The drawer type cooking device according to the present invention has the aforementioned configuration. Therefore, in the cooking device in which the air is supplied into the heating chamber from the back surface of the heating chamber due to installation conditions specific to a large cooking device in which the drawer body is slid relative to the cooking device body by the sliding mechanism outside the heating chamber, the supplied air is caused to descend along the transparent plate despite the shape of a container of an object to be cooked, and the transparent plate can be shielded from the water vapor generated from the object to be cooked, thereby preventing fogging of the transparent plate during cooking. When the splash cover mounted in the cooking device to facilitate cleaning inside the heating chamber is used, the splash cover is provided with a function of preventing the fogging of the transparent plate during cooking by guiding the supplied air to flow as the descending air flow. That is, the supplied air from the back surface of the heating chamber can be caused to flow toward the inner surface of the transparent plate by using the splash cover for facilitating cleaning. Thus, it is not necessary to add a new component such as a dedicated exhaust duct, and the drawer type cooking device can be reduced in production cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an explanatory view illustrating an air flow in a vertical section of a drawer type cooking device;

FIG. 2 is an explanatory view illustrating an air flow in a horizontal section of the drawer type cooking device shown in FIG. 1;

FIG. 3 is a front view of the drawer type cooking device shown in FIG. 1;

FIG. 4 is a side schematic view of a drawer body of the drawer type cooking device shown in FIG. 1;

FIG. 5 is a schematic plan view of the drawer body shown in FIG. 4; and

FIG. 6 is a schematic perspective view of a conventional drawer type cooking device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following, an embodiment of a drawer type cooking device according to the present invention will be described with reference to the accompanying drawings. The cooking device may have the same configuration as that of a conventional cooking device shown in FIG. 6 except for an exhaust air flow, and thus, the description of the configuration will be omitted.

In the drawer type cooking device according to the present invention, as specifically shown in FIG. 3, an air supply and exhaust grill is provided in a lower portion of the front surface of a cooking device body 1. The air supply and exhaust grill includes air supply units 31 and 32 disposed on the both sides in the width direction, and an exhaust unit 33 disposed across the width direction between the both air supply units 31 and 32. The air supply units 31 and 32 include air supply ducts 34 and 35 that extend all the way to the back of the cooking device body 1 in the longitudinal direction as shown in FIGS. 1 and 2. Outside air sucked in through the air supply units 31 and 32 is delivered to a rear space 11 of the cooking device body 1 through the air supply ducts 34 and 35. The exhaust unit 33 will be described in detail later.

A high-voltage transformer 12 for generating a high voltage, a cross-flow fan 13, and a magnetron 14 for generating microwaves based on the high voltage from the high-voltage transformer 12 are disposed sequentially from the bottom to the top in the rear space 11 of a heating chamber 3 of the cooking device body 1. A waveguide tube 15 connected to the magnetron 14 to guide the microwaves extends across a ceiling 16 of the cooking device body 1.

A splash cover 17 for facilitating cleaning inside the heating chamber is provided in an upper portion of the heating chamber 3, that is, in the vicinity of the ceiling 16 of the cooking device body 1. The splash cover 17 is wide enough to cover substantially an entire wall surface 16 a of the ceiling 16, and is disposed at a predetermined distance from the wall surface 16 a of the ceiling 16. Accordingly, a gap passage 18 is formed between the ceiling wall surface 16 a and a top surface 17 a of the splash cover 17. The splash cover 17 also extends to the vicinity of the inner surface of a door 2 a. A gap 19 is thereby formed between a front end 17 b of the splash cover 17 and the inner surface of the door 2 a. The air flowing through the magnetron 14 is delivered into the heating chamber 3 from the back surface of the heating chamber. The air flow then flows toward the front of the cooking device body 1 through the gap passage 18 and flows through the gap 19 by changing its direction at a position blocked by the door 2 a. The air flow flowing through the gap 19 becomes a descending air flow along the inner surface of the door 2 a within the heating chamber 3.

An exhaust window unit 21 for exhausting the descending air flow from the gap 19 is provided at the front of a bottom portion 20 of a drawer body 2, that is, at the front end of a heated object storage unit 2 b that is opposite to the gap 19 in the vertical direction. The exhaust window unit 21 extends substantially across the width of the bottom portion 20 except for the both ends as a coupling part to couple the heated object storage unit 2 b to the door 2 a. An exhaust window 22 penetrating the bottom portion 20 is formed in the exhaust window unit 21. Since the width of the coupling part is smaller than the width of the bottom portion 20, the coupling strength between the door 2 a and the heated object storage unit 2 b is reduced in comparison with a conventional structure in which the drawer body 2 has a closed bottom surface. It is therefore preferable to improve the coupling strength (width and height dimensions, and the strength of a coupling fixture) of the coupling part such that the coupling strength is not reduced. The exhaust window unit 21 may be formed between the bottom portion 20 and the inner surface of the door 2 a by cutting away the front end of a bottom plate which constitutes the bottom portion 20. The exhaust window unit 21 also includes an upright wall 23 that stands at the edge along the exhaust window 22 in the heated object storage unit. The upright wall 23 can effectively guide passage of the descending air flow, and smoothly exhaust the descending air flow including water vapor through the exhaust window unit 21. By providing the upright wall 23, water overflowing from a food (an object to be heated) into the heating chamber 3 can be prevented from flowing out from the exhaust window 22.

An exhaust opening 26 is provided in a body bottom portion 25 of the cooking device body 1 at a position corresponding to the exhaust window unit 21 in the bottom portion 20 of the drawer body 2 when the drawer body 2 is in a pushed-in state. The exhaust opening 26 has an exhaust inlet formed facing the exhaust window 22 when the drawer body 2 is in the pushed-in state within the heating chamber 3. An exhaust duct 36 extends from the exhaust opening 26 in the body bottom portion 25 of the cooking device body 1 to communicate with the exhaust unit 33 in the front surface lower portion of the cooking device body 1. The exhaust duct 36 is an exhaust passage which is bent within the body bottom portion 25 and whose outlet opens to the outside, and can release the air flow including water vapor flowing into the exhaust opening 26 to the outside.

Because of the above configuration, when the cooking device is operated with the drawer body 2 being pushed into the cooking device body 1 and the heating chamber 3 being closed by the door 2 a, the cross-flow fan 13 is driven. Cooling air flows F1 and F1 sucked in from the air supply units 31 and 32 in the front surface lower portion of the cooking device body 1 become flows F2 and F2, and pass through the air supply ducts 34 and 35 formed within the bottom portion of the cooking device body 1. The flows F2 and F2 are thereby delivered backward, and become flows F3 and F3 by changing the direction upward from the backmost portions of the air supply ducts 34 and 35, to reach the rear space 11. The cooing air flow F3 passes through the high-voltage transformer 12 disposed in a lower portion before being sucked into the cross-flow fan 13, thereby cooling the high-voltage transformer 12. An air flow F4 blown out from the cross-flow fan 13 passes through the magnetron 14 disposed above the cross-flow fan 13, thereby cooling the magnetron 14. The air flow delivered into the heating chamber 3 is heated to some extent when passing through the high-voltage transformer 12 and the magnetron 14, to be a high-temperature and dry air flow.

The air flow delivered into the heating chamber 3 from the back surface becomes an air flow F5, and flows forward through the gap passage 18 between the ceiling wall surface 16 a and the top surface 17 a of the splash cover 17. The air flow F5 passes through the gap 19 formed between the front end 17 b of the splash cover 17 and the inner surface of the door 2 a, and flows as a descending air flow F6 along the inner surface of the door 2 a. Since the descending air flow F6 flows along a door glass 10 as a transparent plate, water vapor (a flow Fs1) generated from the object to be heated during cooking is prevented from coming into contact with the door glass.

The descending air flow F6 flowing along the inner surface of the door 2 a engulfs the water vapor generated from the object to be heated, and flows into the exhaust window unit 21 in the bottom portion 20 of the heated object storage unit 2 b (a water vapor flow Fs2). The descending air flow F6 further passes through the exhaust opening 26 in the body bottom portion 25 of the cooking device body 1 and the exhaust duct 36 in the front surface of the cooking device body 1, and is exhausted to outside the cooking device as an exhausted air flow F7 from the exhaust unit 33 of the grill in the front surface lower portion of the cooking device.

As described above, the air is supplied from an upper portion of the back surface of the heating chamber, and the descending air flow is kept flowing along the inner surface of the door 2 a. Therefore, the water vapor generated from the food (the object to be heated) during cooking is guided by the descending air flow to flow out from the exhaust unit 33 through the exhaust window unit 21. A built-in cooking device has a smaller degree of freedom in an air supply and exhaust passage structure in comparison with a cooking device that is installed alone on a countertop or an OTR (over the range) cooking device that is mounted on a wall surface or suspended from a cabinet to be installed above a gas range. It is thus necessary to supply and exhaust air from the air supply and exhaust grill disposed in the front surface lower portion. In the drawer type cooking device according to the present invention, the air supply and exhaust structure is inventively disposed to address such limits, and the air can be exhausted to outside the cooking device from the front surface lower portion of the cooking device.

Also, since the descending air flow having an air curtain effect exists between the door 2 a and the heating chamber 3, the water vapor generated from the object to be heated is prevented from dewing on the door glass 10 of the door 2 a. In such a manner, the water vapor can be prevented from being cooled in contact with the door glass 10 to cause condensation and adhesion of water droplets. Therefore, the door glass 10 is not fogged up, and a user of the cooking device can look into and check the inside of the heated object storage unit 2 b from the outside through the door glass 10.

In comparison with the drawer type cooking device disclosed in Japanese Patent Laid-Open Publication No. 2008-8547, the exhaust passage from the heating chamber is reduced in length, and has less bent portion. Therefore, the blowing load on a cooling fan motor is reduced, and power consumption is thus reduced, which is preferable in view of energy saving. 

1. A drawer type cooking device comprising: a cooking device body having a heating chamber formed therein, the heating chamber having an opening to open at a front; a drawer body capable of being drawn out of and pushed into the heating chamber of the cooking device body; and a sliding mechanism slidably supporting the drawer body on the cooking device body outside the heating chamber; the drawer body comprising a heated object storage unit stored in the heating chamber in a pushed-in state with an object to be heated being loaded thereon, and a door mounted on a front end of the heated object storage unit and capable of closing the opening of the heating chamber in the pushed-in state, the door having a transparent plate for enabling a user to look into the heated object storage unit, wherein an air flow delivered into the heating chamber from a back surface of the heating chamber is caused to descend along an inner surface of the transparent plate of the door, and the descending air flow is exhausted along with water vapor generated by heating the object to be heated from an exhaust unit that opens at a front end of the cooking device body through an exhaust window unit that is formed at the front end of the heated object storage unit.
 2. The drawer type cooking device according to claim 1, further comprising a splash cover disposed with a gap between the splash cover and a ceiling wall of the heating chamber, wherein the air flow is guided to an upper portion of the inner surface of the door through the gap.
 3. The drawer type cooking device according to claim 2, wherein when the drawer body is in the pushed-in state, a front end of the splash cover occupies a position adjacent to the inner surface of the door, thereby forming a gap between the front end of the splash cover and the inner surface of the door to allow the descending air flow to flow down therefrom.
 4. The drawer type cooking device according to claim 1, wherein the exhaust window unit comprises an upright wall for guiding passage of the descending air flow at an edge along an exhaust window that is formed at the front end of the heated object storage unit.
 5. The drawer type cooking device according to claim 1, wherein the exhaust unit of the cooking device body comprises an exhaust inlet formed in a bottom portion of the cooking device body at a position facing the exhaust window unit of the drawer body in the pushed-in state, and an exhaust outlet connected to the exhaust inlet to open at the front end of the cooking device body. 